Apparatus for air disinfection in ventilation system

ABSTRACT

An irradiation module apparatus  100  for use in a duct or conduit  10  of an air ventilation system preferably has a separation panel  1 ; an electronic module  2  for storing a ballast and electronic components mount on an external side of the separation panel  1 ; an irradiation module  5  comprised of a germicidal lamp  3  in a substantially parabolic reflector  4 , the reflector  4  having an aperture  43  for passing filtered air from an air filter module  6 , the lamp  3 , reflector  4 , and an air filter module  6  all being supported on an internal side of the separation panel  1 ; and wherein upon assembly to the conduit  10 , the irradiation module apparatus  100  is passed into an opening  9  cut in the conduit  10  until the separation panel  1  can cover the opening  9  and be fastened to conduit  10 , thereby positioning the irradiation module  5  and the filter module  6  in the air path of the conduit  10  or duct.

TECHNICAL FIELD

The present invention relates to air and gas purification and in particular sterilization or disinfection by irradiation with an ultraviolet radiation source.

BACKGROUND OF THE INVENTION

The airborne transmission of bacteria and viruses, chiefly respiratory disease organisms is a serious problem in health care. The control of airborne disease transmission has become increasingly important with an increasing number of people growing older with weakened immune systems more vulnerable to airborne disease or infected with human immunodeficiency virus (HIV) or other airborne and difficult to cure diseases. This coupled with antibiotic resistant strains of bacteria have created a need for inexpensive, efficient air purification systems. The spread of air born infections can be reduced by killing the infectious microorganism by ultraviolet (UV) radiation. Ultraviolet radiation to destroy airborne microorganisms can be used inside ventilation system air duct.

The continuing spread of tuberculosis (TB) infection and other airborne disease in modern health institutions, correctional institutions, and shelters for homeless indicates however, that the known air purification systems are inadequate in controlling the spread of airborne microorganisms.

The sterilization by ultraviolet radiation has been known for many years.

Various methods and apparatus have been invented for ultraviolet irradiating fluids, air and water in particular, in order to control the spread of microorganisms by destroying those microorganisms with a sufficient dose of radiation.

Air purification by means of filtration and irradiation is widely practiced.

Conventional air cleaning systems commonly have a filtration and irradiation units.

Conventional UV fluid sterilization systems have relied on exposure of suspended microorganisms to ultraviolet radiation by passing medium over or around one or more ultraviolet lamps. This method is used in U.S. Pat. Nos. 5,112,370 and 5,200,156. This method has a number of shortcomings.

The first shortcoming of the previous art is their low reliability. The particles suspended in the fluid accumulate on the surface of the lamp or protective tubes, forming the UV light absorption layer, which restricts or eliminates the germicidal effectiveness. The reliability and actual germicidal effectiveness depend on the quality of the medium filtration and come very small and unpredicted if the medium is unfiltered or poorly filtered.

The second shortcoming of previous art of UV sterilization systems is that they have low efficiency of use of the UV energy, because their lamps accumulate particles on the surface from the beginning and because in ducts or pipes with ratio length-L to diameter-DL/D=10:1 only 6% of beams have their path length equal to the longest available way (L/2 that is when the lamp is placed halfway between the longest straight line length of the duct (L), the maximum available way is only L/2), other beams, 94% are directed on much shorter paths and could irradiate smaller volume on its way and hence less efficient.

The third shortcoming of previous art is nonuniform irradiation intensity in an irradiated volume. In the device for sterilization according to U.S. Pat. No. 5,200,156 the author tried to achieve more uniform irradiation intensity than before by applying a flat oval cross section light source with or without the reflectors. But this invention made limited progress because the according to the U.S. Pat. No. 5,200,156 can irradiate towards axis of pipe only 50% of radiation and only 6% of the beams will have length equal to the length of the longest available way. Other beams are short slanting beams. They irradiate smaller volume than longest beams and are absorbed by the pipe walls. Due to the early absorption, the efficiency of the use of short slanting beams is very low. As a result the efficiency of all previous art, including the sterilizer according to U.S. Pat. No. 5,200,156 is too low.

The fourth shortcoming of previous art according to U.S. Pat. No. 5,200,156 is that the sources of radiation are installed inside the medium flow, liquid or gas, and create a substantial pressure loss in the system. To retrofit an operating ventilation or other system with known UV sterilization system it is necessary to replace a fan, pump, electric motor by more powerful ones. As a result capital and operating expenses would increase.

In U.S. Pat. No. 5,635,133, the above mentioned shortcomings were eliminated by an apparatus invented by Dr. Mark Glazman that increased the efficiency of the germicidal radiation for killing microorganisms by first providing a secondary flow of particle free fluid that maintained the surfaces of the means for transferring and orienting the germicidal beams free of energy absorbing dust particles and by secondarily orienting the germicidal beams of radiation into an array of parallel beams which when passed though a duct containing a primary flow of air flow achieved a very high efficiency due to the orientation of the beams being generally parallel to the duct path.

This apparatus should be placed on the bottom of horizontal ventilation duct or on the support inside of vertical duct. For yearly maintenance the access door should be attached to the duct. A short coming of this prior art device was the installation required significant amounts of sheet metal work.

Another shortcoming of this prior art device was the dust accumulation on peripheral part of lower half faucet of the reflector, which reduces the reflectivity and germicidal power of the device over time.

This apparatus utilized an ultraviolet lamp and a substantially parabolic reflector to achieve these improvements in combination with other elements.

SUMMARY OF THE INVENTION

An irradiation module apparatus for use in a duct or conduit of an air ventilation system preferably has a separation panel; an electronic module for storing a ballast and electronic components mount on an external side of the separation panel; an irradiation module having a germicidal lamp in a substantially parabolic reflector, the reflector having an aperture for passing filtered air from an air filter module, the irradiation module and an air filter module all being supported on an internal side of the separation panel; and wherein upon assembly to the conduit, the irradiation module apparatus is passed into an opening cut in the conduit until the separation panel can cover the opening and be fastened to conduit, thereby positioning the irradiation module apparatus in the symmetric streamline position in the air path of the conduit or duct.

The irradiation module apparatus has the lamp placed in a lamp holder on an end adjacent the separation panel for mechanically holding and electronically energizing the lamp.

The irradiation module apparatus also has the reflector having sides or ends that are not air penetrable.

The irradiation module apparatus wherein the irradiation module and filter module are cantilevered and supported on the internal side of the separation panel and the electronic module affixed on external side of the separation panel.

The irradiation module apparatus has the smooth panels enclosing the irradiation module and the filter module, the smooth panels are attached to the separation panel on one side and to end panel on another side, and to reflector in the front and filter module in the back for preventing the settling of dust on the peripheries of the reflector and maintaining high germicidal efficiency, by providing even stream conditions along both smooth panels.

It is an object of the invention to provide an apparatus for killing microorganisms in the air flow, the apparatus having: the air flow; the conduit for passing the air flow; the irradiation module apparatus for killing microorganisms; an irradiation module apparatus being immersed in the air flow and being having sealed by air impenetrable material on both sides; an air filtration module having input chamber and output chamber, input aperture, output aperture and a filter for passing a secondary air flow, the secondary air flow being substantially particles free, the secondary air flow running along or flowing across the ultraviolet lamp and the parabolic reflector and establishing a substantially particulate free barrier environment maintaining clean the ultraviolet lamps and reflector; electronic module having electrical ballast, receptacle, wiring, switch and electrical cord for energizing the ultraviolet lamps; a separation panel for tightly covering of the opening in the conduit for passing the air flow and for a mounting of irradiation, filtration and electronic modules; the smooth panels enclosing the irradiation module and the filter module, the smooth panels are attached to the separation panel on one side and to end panel on another side, and to the reflector in the front and to the filter module in the back for preventing the settling of dust on the peripheries of the reflector maintaining high germicidal efficiency.

Preferably the irradiation module for killing microorganisms has one or more ultraviolet lamps and substantially parabolic cylindrical reflectors open along the reflection path. The side walls of the irradiation module cylindrical reflectors are sealed with air not penetrable walls. The irradiation module is mounted on the inside surface of the separation panel. The ultraviolet lamps emit an ultraviolet radiation in the air flow and are well known as the most effective source of germicidal radiation.

Preferably the substantially parabolic reflectors have mirror like surface for orienting the emission of the ultraviolet radiation into a substantially parallel array of beams. The substantially parallel array of the beams provides most effective use of the ultraviolet energy.

Preferably the substantially parabolic reflector for orienting the ultraviolet beams is provided with the arc of ultraviolet lamp situated in its focus.

Preferably electronic module has electrical ballast, lampholder, wiring, switch and electrical cord for energizing the ultraviolet lamps. The electronic module is situated outside of the conduit on outside surface of the separation panel.

Preferably the conduit for passing of the air flow along a path aligned with the array of parallel ultraviolet beams is provided, the path being of sufficient length to allow the array of beams of ultraviolet radiation to kill microorganisms.

Preferably the conduit for passing of the air flow is a straight prime conduit. The irradiation module is situated at the end of the straight prime conduit and is faced at the straight prime conduit.

Preferably the inside surface of irradiation module have a form of parabolic cylinder enclosed on both sides by air impenetrable wall and open along the reflection path.

Preferably the substantially parabolic reflector has an aperture open to the secondary flow and connected with output aperture of the filtration module.

Preferably the filtration module for passing the secondary air flow has a filter, the filter being sufficient to remove particles from the secondary air flow. The secondary flow is running along the substantially parabolic reflector and the lamp located in the reflector cavity and establishing a substantially particulate free barrier environment maintaining the surfaces of the substantially parabolic reflector and lamp clean.

Preferably the smooth panels enclose the irradiation module and the filter module, the smooth panels are attached to the separation panel on one side and to end panel on another side, and to the reflector in the front and to the filter module in the back for preventing the settling of dust on the peripheries of the reflector and maintaining high germicidal efficiency, by providing even stream conditions along both smooth panels.

The secondary air flow is a small part of the air flow and the filter to remove particles the secondary flow is also small and inexpensive. The flow through the filter is very small and has the velocity 0.1-0.25 m/sec, (20-50 FPM) and the life time of the filter is a few times longer than the life time of a filter which conventionally is used for the filtration of the prime flow with the velocity 1.27 m/sec (250 FPM). As a result the ultraviolet lamps and the reflector remain clean independently of the purity of the air flow, the period between the maintenances is much longer, and the reliability of the apparatus is higher than previously known arts.

The unit for air disinfection in the ventilation duct is estimated to be about five times more efficient after one month of operation than conventional unit having bore ultraviolet lamp the same wattage.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained by way of example only and with reference to the following drawings wherein:

FIG. 1 is a schematic view of a preferred embodiment of the invention showing an apparatus for air disinfection in ventilation system with a vertical cross-sectional view taken along axis of the conduit for passing the air flow to expose the components of the apparatus for air disinfection in ventilation system;

FIG. 2 is a schematic view of a preferred embodiment of the invention showing an apparatus for air disinfection in ventilation system and all its components.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides an irradiation module apparatus for air disinfection in ventilation system, generally referred to by reference 100. The preferred embodiment of the invention is shown in FIG. 1 and FIG. 2. The means for passing the air flow is the straight prime conduit 10.

The irradiation module 5 includes the parabolic reflector 4, not penetrable walls 41, 42 and the ultraviolet lamp 3. The parabolic reflector 4 is located inside the straight prime conduit 10. The arc of the ultraviolet lamp 3 is situated in the focus of the parabolic reflector 4 by the lamp holder 33. The lamp holder 33 is mounted on the separation panel 1. The irradiation module 5 having parabolic reflector 4 is installed such that its axis or axis plane is parallel to the axis or axis plane of the straight prime conduit 10. The parabolic reflector 4 has an aperture 43.

As shown, the reflector 4 is substantially parabolic over most of its surface. At the extremities the surface may be elliptical. As shown the reflector 4 is having side walls 41, 42. The irradiation module contacts at the aperture 43 location the external surface of the filter module 6 creating a close fitting arrangement. The reflector is attached to the walls 41, 42 by means of spot welds or threaded fasteners.

According to the preferred embodiment, the filter module 6 includes input chamber 61 and output chamber 62, input aperture 63, output aperture 64 and a filter 7 for passing the secondary air flow 21. The intake aperture 63 is connected and opens to the air flow moving inside of straight prime conduit 10. The filter 7 separates the intake chamber 61 from output chamber 62. The output aperture 64 is connected with the aperture 43 of the parabolic reflector 4 preferably the apertures 64 and 42 are narrow, long slits extending along the entire length of the lamp 3. The filter 7 is an effective particulate filter. In case of the air filtration the high efficiency particulate filters or electrostatic filter could be used but the application of other filters is not limited.

According to the proffered embodiment the smooth panels 22, 23 enclose the irradiation module 5 and the filter module 6; the smooth panels 22 and 23 are attached to the separation panel 1 on one side and to end panel 42 on another side, and to the reflector 4 in the front and to the filter module 6 in the back for preventing the settling the dust on the peripheries of the reflector 4 and maintaining high germicidal efficiency, by providing even stream conditions along both smooth panels 22 and 23.

As shown in FIG. 2, according to the preferred embodiment the electronic module 2 contains the lamp holder 33, electrical cord 8, electrical ballast and switch (neither being shown) for energizing the ultraviolet lamps. The electronic module 2 is situated outside of the conduit 10 on outside surface of the separation panel 1. Not shown is the associated wiring and connections needed to provide electricity to the ballast and ultimately the lamp as these features are commonly understood by those of ordinary skill in the art. The lamp 3 itself is held in place by a lamp holder 33. The lamp holder 33 provides both a mechanical means for securing the lamp 3 and electrical connectors for energizing the lamp 3, and germicidal beams for killing the microorganisms.

According to the preferred embodiment, the irradiation module apparatus 100 for air disinfection in ventilation system is realized as shown in FIG. 1. The air flow 20 is coming through the straight prime conduit 10. The secondary flow 21 is a small part of the air flow 20 and goes through the filtration module 6 including the effective particulate filter 7. This particle filter 7 of a filtration size recommended to be like a “HEPA” type, effective for capturing dust particles of a size 0.3 micron or bigger. The filter 7 captures and arrests the particles suspended in the secondary flow medium 21. The clean secondary air flow, coming through the apertures 64 and 43 contacts the reflector 4, and the envelope or outer surface of ultraviolet lamp 3, and protects the envelope of ultraviolet lamp 3 and the reflector 4 from the accumulation of the particles from the air flow 20. This filtered air fills the space defined by the reflector 4 and over the ultraviolet lamp 3 thus providing a particle-free barrier of secondary flow 21 protecting the surfaces of these ultraviolet lamps 3 and parabolic reflectors 4 from the duct.

At the same time the arc of the ultraviolet lamp 3 emits the germicidal beams for killing microorganisms. The envelope of the ultraviolet lamp 3 transfers the germicidal beams to the parabolic reflector 4. Due to the parabolic shape and the situation of the arc of the ultraviolet lamp 3 in the focus of the parabolic reflector 4, the parabolic reflector 4 orients the germicidal beams into a substantially parallel array of beams. The straight prime conduit 10 pass the air flow 20 along a path aligned with the array of the substantially parallel germicidal beams.

The substantially parallel array of the germicidal beams maximizes and uniformly radiates the air flow 20 passing the straight prime conduit 10. The microorganisms suspended in the air absorb the substantially parallel arrays of beams, are killed or substantially damaged before passing the end of the straight prime conduit 10.

As further illustrated in FIGS. 1 and 2, the irradiation module apparatus 100 has the electronic module 2 attached to the separation panel 1 and positioned external of the duct 10. This means any electrical component needing replacement can be accomplished by simply removing the cover on the electronic module 2 exposing these components. The separation panel 1 as shown in FIG. 2 has four openings 91 that can have threaded fasteners such as sheet metal screws pass through to attach the apparatus 100 to a wall of the conduit as shown in FIG. 2. The conduit 10 has an opening cut through sufficiently large to accept the irradiation module 5 and filter module 6. Upon assembly the irradiation module apparatus 100 is simply inserted until the separation panel 1 abuts the wall of the conduit 10 and is simply fastened to the conduit through the openings 91 in the separation panel 1. The opening in the conduit 10 cut at sufficient distance from upper wall 11 and lower wall 12 of the conduit 10 thereby positioning the irradiation module 5 and filter module 6 being suspended in the air path of the conduit 10, at sufficient distance from the lower wall 12 and upper wall 11 of the conduit 10 to establish even stream conditions along both smooth panels 22, 23 to keep peripherals of the reflector 4 clean, and to maintain high germicidal efficiency. Once this is accomplished, the electrical connector 8 simply needs to be connected to a power receptacle and the air purification is activated internal of the conduit 10.

The replacement of the germicidal lamp 3 and filter 7 are designed to last 12 months after which time the effectiveness of the lamp 3 will drop off and the filter 7 will begin to become blocked depending on the amount of dust captured. Exchange of both the lamp 3 and filter 7 is accomplished by simply unplugging the cord 8 and removing the four fasteners and pulling the apparatus 100 out of the duct 10 and replacing these parts, lamp 3 and filter 7. This greatly simplifies the maintenance of the apparatus 100 and insures the device performs at very high levels of efficiency.

Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims. 

1. An irradiation module apparatus for use in a duct or conduit of an air ventilation system comprises: a separation panel; an electronic module for storing a ballast and electronic components mount on an external side of the separation panel; an irradiation module having a germicidal lamp enclosed in a substantially parabolic reflector, the reflector having an aperture for passing filtered air from an air filter module, the irradiation module and an air filter module all being supported on an internal side of the separation panel; smooth panels enclosing irradiation module and filter module, the smooth panels are attached to the separation panel on one side and to end panel on another side, and to the reflector in the front and to the filter module in the back; and wherein upon assembly to the conduit, the irradiation module apparatus is passed into an opening in the conduit until the separation panel can cover the opening and be fastened to conduit, thereby positioning the irradiation module and filter module being suspended in the air path of the conduit or duct, at sufficient distance from the surface of the conduit or duct to establish even stream conditions along both smooth panels to keep peripherals of the reflector clean, and to maintain high germicidal efficiency.
 2. The irradiation module apparatus of claim 1 wherein the lamp is placed in a lamp holder on an end adjacent the separation panel for mechanically holding and electronically energizing the lamp.
 3. The irradiation module apparatus of claim 1 wherein the reflector has two sides or ends that are not air penetrable.
 4. The irradiation module apparatus of claim 1 wherein the apparatus has the lamp reflector and air module cantilevered and supported on the internal side of the separation panel and the electronic module affixed on external side of the separation panel.
 5. The irradiation module apparatus of claim 1 wherein the irradiation module and filter module suspended in the air path of the conduit or duct, at the distance from the surface of the conduit or duct being 0.5 inch to 5 inch.
 6. An apparatus for air disinfection in ventilation system using a germicidal beams for killing microorganisms in a straight portion of the air flow containing particles and microorganisms, the apparatus characterized by: a straight prime conduit for passing said primary air flow; an irradiation module for killing microorganisms being immersed in said air flow; a parabolic cylindrical reflector for orienting germicidal beams for killing microorganism being located inside of irradiation module, the ultraviolet lamp with the arc situated in the focus of the parabolic cylindrical reflector, the germicidal beams for killing microorganisms being oriented in an array of substantially parallel germicidal beams aligned along the flow path of the air in the straight prime conduit; an electronic module for energizing said means for killing microorganisms; a filtration module for passing a secondary flow of a substantially particle free portion of said primary air flow; wherein said primary flow, said straight prime conduit, said filtration module and said irradiation module causes said secondary flow to run along or flow across the surface of said ultraviolet lamps and parabolic cylindrical reflectors to establish a substantially particulate free barrier environment maintaining clean said ultraviolet lamps and said parabolic cylindrical reflectors.
 7. The apparatus for air disinfection in ventilation system of claim 6 wherein said filter module attached to irradiation module for passing said secondary air flow trough the aperture located at the vertex line of said parabolic cylindrical reflectors.
 8. The apparatus for air disinfection in ventilation system of claim 6 wherein said irradiation module has one or more arcs of ultraviolet lamps which emit ultraviolet beams. 